It was about 4:20 p.m. on March 17, 1960, when people living near the southern Indiana town of Tell City heard two big booms that sounded like explosions high in the air.

Cyrl Powers, a farmer, was outdoors near his barn. "I looked up and saw this wing falling through the air," Powers told The Star later that day. "Then I looked again and saw the body of the plane falling … it sort of came straight down like a rock."

When he and others ran to the crash site they found nothing but a huge crater and scattered bits of debris. "There wasn't hardly a piece big enough to hold in your hand," Powers said.

Farmers view the scene of the crash of a Northwest Airlines Electra the day after the jet exploded and crashed.(Photo: Ed Lacey)

The plane was Flight 710, a Lockheed Electra turboprop on its way from Chicago to Florida carrying 57 passengers, including three from South Bend, and a crew of six. One wing and two engines were found five miles away, but at the main crash site there was little more than a crater 20 feet deep and 40 feet across.

Shreds of clothing and paper blew in the wind and collected in trees. There were no bodies. Another farmer, Ted Wilson, told The Star what he saw amid the debris: "Pieces of flesh – little pieces – were scattered all around. But I didn't see a piece that could be identified as a body, not even anything large enough to look like a man's limb."

For weeks, investigators and medical personnel gathered what they could and made a few victim identifications through dental records, but in an era before DNA sampling most of the 63 people were never identified except through the plane's passenger manifest. The crater was eventually bulldozed over and a monument was erected on the spot.

Police and fire officials look at the crater caused when Northwest Airlines Flight 710 slammed, nearly head-on at nearly 600 mph into a field a mile from the Ohio River near Cannelton and Tell City.(Photo: file)

As for the cause of the crash, some were convinced it had been a bomb. Crash investigators soon dismissed that theory. It was already known that severe turbulence had been reported in that stretch of air space on that day, but that shouldn't have been enough on its own to rip a plane's wing off. Lockheed engineers identified a design weakness that made the Electra susceptible to a "freak vibration phenomenon" that shook loose engine mounts and caused the wing to fail structurally. The Civil Aeronautics Board agreed in its final report issued more than a year after the crash.